Export of internal Abseil changes.

--
b0015627610a311997ab21b8b295a8168b5915ec by Derek Mauro <dmauro@google.com>:

Add an empty log_severity library. The log_severity sources will
eventually migrate here once users are updated to depend on the new
target.

Note that no opensource user should be depending on log_severity.h
today since it has no purpose in opensource.

PiperOrigin-RevId: 258781702

--
c4d8d03f731d1de648ef2d17a55c3a16029ba331 by Derek Mauro <dmauro@google.com>:

Move atomic_hook.h to its own internal target.

PiperOrigin-RevId: 258765527
GitOrigin-RevId: b0015627610a311997ab21b8b295a8168b5915ec
Change-Id: I0ec9b8b3cb6a27dc32a5f6c318d07e02548f193d

4 files changed, 40 insertions, 4 deletions

diff --git a/absl/base/BUILD.bazel b/absl/base/BUILD.bazel
index 5b7b295a6f9b..1cdd1909b3ae 100644
--- a/absl/base/BUILD.bazel
+++ b/absl/base/BUILD.bazel
@@ -28,6 +28,22 @@ package(default_visibility = ["//visibility:public"])
 licenses(["notice"])  # Apache 2.0
 
 cc_library(
+    name = "atomic_hook",
+    hdrs = ["internal/atomic_hook.h"],
+    copts = ABSL_DEFAULT_COPTS,
+    linkopts = ABSL_DEFAULT_LINKOPTS,
+    visibility = [
+        "//absl:__subpackages__",
+    ],
+)
+
+cc_library(
+    name = "log_severity",
+    copts = ABSL_DEFAULT_COPTS,
+    linkopts = ABSL_DEFAULT_LINKOPTS,
+)
+
+cc_library(
     name = "spinlock_wait",
     srcs = [
         "internal/spinlock_akaros.inc",
@@ -143,7 +159,6 @@ cc_library(
     hdrs = [
         "call_once.h",
         "casts.h",
-        "internal/atomic_hook.h",
         "internal/cycleclock.h",
         "internal/low_level_scheduling.h",
         "internal/per_thread_tls.h",
@@ -161,10 +176,12 @@ cc_library(
         "//conditions:default": ["-pthread"],
     }) + ABSL_DEFAULT_LINKOPTS,
     deps = [
+        ":atomic_hook",
         ":base_internal",
         ":config",
         ":core_headers",
         ":dynamic_annotations",
+        ":log_severity",
         ":spinlock_wait",
         "//absl/meta:type_traits",
     ],
@@ -177,7 +194,7 @@ cc_test(
     copts = ABSL_TEST_COPTS,
     linkopts = ABSL_DEFAULT_LINKOPTS,
     deps = [
-        ":base",
+        ":atomic_hook",
         ":core_headers",
         "@com_google_googletest//:gtest_main",
     ],
@@ -536,6 +553,7 @@ cc_test(
     linkopts = ABSL_DEFAULT_LINKOPTS,
     deps = [
         ":base",
+        ":log_severity",
         "@com_google_googletest//:gtest_main",
     ],
 )
diff --git a/absl/base/CMakeLists.txt b/absl/base/CMakeLists.txt
index 34bfba27d55d..f27e121e2553 100644
--- a/absl/base/CMakeLists.txt
+++ b/absl/base/CMakeLists.txt
@@ -16,6 +16,22 @@
 
 absl_cc_library(
   NAME
+    atomic_hook
+  HDRS
+    "internal/atomic_hook.h"
+  COPTS
+    ${ABSL_DEFAULT_COPTS}
+)
+
+absl_cc_library(
+  NAME
+    log_severity
+  COPTS
+    ${ABSL_DEFAULT_COPTS}
+) 
+
+absl_cc_library(
+  NAME
     spinlock_wait
   HDRS
     "internal/scheduling_mode.h"
@@ -112,7 +128,6 @@ absl_cc_library(
   HDRS
     "call_once.h"
     "casts.h"
-    "internal/atomic_hook.h"
     "internal/cycleclock.h"
     "internal/low_level_scheduling.h"
     "internal/per_thread_tls.h"
@@ -134,6 +149,7 @@ absl_cc_library(
   COPTS
     ${ABSL_DEFAULT_COPTS}
   DEPS
+    absl::atomic_hook
     absl::base_internal
     absl::config
     absl::core_headers
@@ -227,7 +243,7 @@ absl_cc_test(
   COPTS
     ${ABSL_TEST_COPTS}
   DEPS
-    absl::base
+    absl::atomic_hook
     absl::core_headers
     gtest_main
 )
diff --git a/absl/synchronization/BUILD.bazel b/absl/synchronization/BUILD.bazel
index 67da9d462b0e..fca8cb697af1 100644
--- a/absl/synchronization/BUILD.bazel
+++ b/absl/synchronization/BUILD.bazel
@@ -78,6 +78,7 @@ cc_library(
     deps = [
         ":graphcycles_internal",
         "//absl/base",
+        "//absl/base:atomic_hook",
         "//absl/base:base_internal",
         "//absl/base:config",
         "//absl/base:core_headers",
diff --git a/absl/synchronization/CMakeLists.txt b/absl/synchronization/CMakeLists.txt
index 6fdbcb28391d..4b708823152f 100644
--- a/absl/synchronization/CMakeLists.txt
+++ b/absl/synchronization/CMakeLists.txt
@@ -55,6 +55,7 @@ absl_cc_library(
     ${ABSL_DEFAULT_COPTS}
   DEPS
     absl::graphcycles_internal
+    absl::atomic_hook
     absl::base
     absl::base_internal
     absl::config